scholarly journals Taxonomic diversity and distinctness indices in assessment of weed communities

2012 ◽  
Vol 64 (4) ◽  
pp. 251-258
Author(s):  
Magdalena Jastrzębska ◽  
Maria Wanic ◽  
Wiesław P. Jastrzębski ◽  
Marta K. Kostrzewska
Keyword(s):  
Crop Rotation ◽  
Spring Barley ◽  
Taxonomic Diversity ◽  
Diversity Indices ◽  
Barley Grain ◽  
Taxonomic Distinctness ◽  
Weed Species ◽  
Winter Triticale ◽  
Weed Communities ◽  
Barley Crop

This paper contains an analysis of taxonomic weed biodiversity in the cultivation of spring barley in the period of 1990-2004, grown in crop rotation after potato with a 25% share of this cereal (potato - spring barley - field pea - winter triticale) as well as in crop rotation with its 75% share (potato - spring barley - spring barley - spring barley) in which barley was grown once and twice after the same barley crop. No weed control was used in the present experiment. Every year in the spring (at full emergence of the cereal crop) and before harvest, the species composition and the numbers of individual weed species were determined, as well as weed biomass before harvest. On this basis, the taxonomic diversity and distinctness indices were calculated. Potato/barley crop rotation with a 25% share of this cereal and growing spring barley once and twice after the same barley crop did not differentiate taxonomic weed biodiversity. However, it was positively correlated with rainfall abundance during the growing season and negatively correlated with mean temperature. The taxonomic diversity indices were positively correlated with species richness and species diversity, whereas the taxonomic distinctness indices did not generally show any relationship with these measures. Spring barley grain yield did not depend on taxonomic biodiversity of weed communities.

scholarly journals An attempt to use functional diversity indices for the assessment of weed communities

2012 ◽  
Vol 65 (1) ◽  
pp. 129-140 ◽  
Author(s):  
Magdalena Jastrzębska ◽  
Maria Wanic ◽  
Marta K. Kostrzewska ◽  
Kinga Treder ◽  
Janusz Nowicki
Keyword(s):  
Crop Rotation ◽  
Functional Diversity ◽  
Spring Barley ◽  
Diversity Indices ◽  
Weed Species ◽  
Winter Triticale ◽  
Weed Communities ◽  
Functional Diversity Indices ◽  
Barley Crop

This paper presents an analysis of changes in functional diversity of weeds in spring barley grown in the period 1990-2004 in crop rotation after potato with a 25% share of this cereal (potato - spring barley - field pea - winter triticale) as well as in crop rotation with its 75% share (potato - spring barley - spring barley - spring barley) in which barley was grown once and twice after the same barley crop. No weed control was used in the present experiment. Every year in the spring (at full emergence of barley) and before harvest, the species composition and numbers of individual weed species were determined, as well as their weed biomass before harvest. On this basis, the selected functional diversity indices were calculated. Multidimensional techniques were used for dividing weeds into functional groups and for the determination of some of the indices. Potato/barley crop rotation with a 25% share of barley and growing spring barley once and twice after the same barley crop did not differentiate weed functional biodiversity. The weed functional diversity indices showed different variations over time. Higher variation was usually observed for the indices calculated for the summer communities compared to the spring ones. The strength and significance of the positive correlation between weed functional diversity and precipitation in the growing season and of the negative correlation with mean temperature for the period from April to August were dependent on the measure of diversity. The functional diversity indices showed high convergence. The FD and FAD indices proved to be interchangeable.

scholarly journals Influence of crop rotation and meteorological conditons on biodiversity of weed communities in spring barley (Hordeum vulgare L.)

2012 ◽  
Vol 63 (1) ◽  
pp. 221-233 ◽  
Author(s):  
Magdalena Jastrzębska ◽  
Maria Wanic ◽  
Marta K. Kostrzewska
Keyword(s):  
Crop Rotation ◽  
Spring Barley ◽  
Chenopodium Album ◽  
Diversity Indices ◽  
Weed Species ◽  
Hordeum Vulgare L ◽  
Winter Triticale ◽  
Weed Diversity ◽  
Species Diversity Indices ◽  
Density And Biomass

The paper presents the analysis of changes in weed biodiversity in spring barley cultivated in the years 1990-2004 in crop rotation with a 25% proportion of this cereal (potato - spring barley - sowing peas - winter triticale), when it was grown after potato, and in crop rotation with its 75% proportion (potato - spring barley - spring barley - spring barley), when it was grown once or twice after spring barley. In the experiment, no weed control was applied. Every year in the spring (at full emergence of the cereal) and before the harvest, the composition of weed species and numbers of particular weed species were determined, and before the harvest also their biomass. On this basis, the constancy of species in particular years, Shannon-Wiener species diversity indices and diversity profiles according to Rényi were determined. Weed species richness increased linearly at all plots during the 15-year period. <i>Chenopodium album</i> was a constant and dominant species in terms of weed species density and biomass year after year. The quality of the plot had no clear influence on the diversity of weeds in barley. Weed density and biomass showed high year-to-year variability and a positive correlation with the amount of precipitation and a negative correlation with temperature during the period of the study. The significance of the correlation between the productivity of barley and weed diversity was not confirmed.

Weed species diversity in spring barley varies with crop rotation and tillage, but not with nutrient source

Weed Science ◽  
1997 ◽  
Vol 45 (6) ◽  
pp. 798-806 ◽  
Author(s):  
F. Craig Stevenson ◽  
Anne Légère ◽  
Régis R. Simard ◽  
Denis A. Angers ◽  
Denis Pageau ◽  
...  
Keyword(s):  
Species Richness ◽  
Species Diversity ◽  
Crop Rotation ◽  
Spring Barley ◽  
Climatic Conditions ◽  
Dairy Manure ◽  
Weed Species ◽  
Nutrient Source ◽  
Weed Communities ◽  
Weed Species Richness

The development of sustainable farming systems depends on our ability to predict and manage the response of weed communities to changes in cropping practices. A study was established at Normandin, Québec, Canada, to investigate the influence of liquid dairy manure and mineral fertilizer, as well as chisel and moldboard plow tillage systems, in a spring barley monoculture and a 3-yr spring barley-forage rotation that included red clover and timothy. Weed species richness (Margalef's DMG), evenness (Shannon's E), and diversity (Shannon's H') were examined in these treatments from 1992 to 1995. Nutrient source had no effect on any of the three diversity indices. Evenness values were extremely low in all years, suggesting dominance of a few weed species in most treatments. Weed species richness and diversity generally were greater in the barley-forage rotation compared with the monoculture. Tillage effects on richness and diversity varied with crop rotation. Margalef's DMGand Shannon's H' were greater in 1993 and 1995, but they were lower in 1994 when chisel was compared with moldboard plowing in the monoculture. In 1994, chickweed density was about five times greater in the chisel-plowed monoculture compared with other treatment combinations of rotation and tillage. In 1995, only one species with a density of six plants m−2occurred in the moldboard-plowed monoculture compared with three to six species and densities of 51 to 832 plants m−2in the other rotation by tillage treatments. Climatic conditions and herbicide use patterns in the different crop rotation treatments may have contributed to the more dynamic nature of weed species diversity in the barley monoculture. Reduced frequency of tillage and herbicide application; management of the forage stands, especially with regard to their termination; and improved soil resource availability likely explained the increased but more stable diversity of the weed communities in the barley-forage rotation.

scholarly journals Influence of crop rotation and meteorological conditons on density and biomass of weeds in spring barley (Hordeum vulgare L.)

2012 ◽  
Vol 63 (1) ◽  
pp. 213-220
Author(s):  
Maria Wanic ◽  
Magdalena Jastrzębska ◽  
Marta K. Kostrzewska
Keyword(s):  
Crop Rotation ◽  
Negative Correlation ◽  
Spring Barley ◽  
Weed Species ◽  
Hordeum Vulgare L ◽  
Weed Biomass ◽  
Weed Density ◽  
Winter Triticale ◽  
Weed Infestation ◽  
Density And Biomass

The paper presents the analysis of changes in weed infestation in spring barley cultivated in the years 1990-2004 in crop rotation with a 25% proportion of this cereal (potato - spring barley - sowing peas - winter triticale), when it was grown after potato, and in crop rotation with its 75% proportion (potato - spring barley - spring barley - spring barley), when it was grown once or twice after spring barley. In the experiment, no weed control was applied. Every year in the spring (at full emergence of the cereal) and before the harvest, the composition of weed species and weed density of particular weed species were determined, and before the harvest also their biomass. Weed density increased linearly on all plots during the 15-year period. The average values confirm the increase in weed biomass in the case when spring barley was grown once or twice after this crop; however, those differences were influenced by the previous situation only during some seasons. Weed density and biomass showed high year-to-year variability and a positive correlation with the amount of precipitation and a negative correlation with temperature during the period of the study. A negative correlation between the yield of barley and weed biomass was shown.

scholarly journals Weed infestation of a cereal-legume mixture depending on its concentration and position in a crop rotation

2012 ◽  
Vol 65 (3) ◽  
pp. 99-108
Author(s):  
Marta K. Kostrzewska ◽  
Maria Wanic ◽  
Magdalena Jastrzębska
Keyword(s):  
Species Composition ◽  
Crop Rotation ◽  
Spring Barley ◽  
Similarity Index ◽  
Floristic Composition ◽  
Field Pea ◽  
Total Biomass ◽  
Weed Species ◽  
Weed Communities ◽  
Weed Infestation

A field study was carried out in the period 2000-2006 at the Experimental Station in Tomaszkowo belonging to the University of Warmia and Mazury in Olsztyn. Its aim was to compare weed infestation of a mixture of spring barley and field pea grown in a four crop rotation with different crop selection and sequence. Each year during tillering of spring barley and before the harvest of the mixture, weed species composition and density were evaluated, while additionally weed biomass was also estimated before the harvest. These results were used to determine species constancy, Simpson&rsquo;s dominance index, the Shannon-Wiener diversity and evenness indices as well as the community similarity index based on floristic richness, numbers and biomass of particular weed species. The cropping frequency and the position of the mixture in the crop rotation did not differentiate the species composition and total biomass of weed communities in the cereal-legume mixture crops. The crop rotation in which the mixture constituted 50% and was grown after itself had a reducing effect on weed numbers. Growing field pea in the 4-year crop rotation promoted weed infestation of the mixture and the dominance of weed communities. <em>Capsella bursa-pastoris</em>, <em>Chenopodium album</em>, <em>Echinochloa crus-galli</em>, <em>Elymus repens</em>, <em>Polygonum convolvulus</em>, and <em>Sonchus arvensis </em>were constant components of the agrophytocenoses. The weed communities were more similar in terms of their floristic composition than in terms of weed density and air-dry weight of weeds.

scholarly journals Change of the productive soil moisture amount under different agrophytocenoses in accordance with the used tillage system in short-term crop rotation

2021 ◽  
pp. 131-144
Author(s):  
I. Prymak ◽  
M. Yermolaev ◽  
O. Panchenko ◽  
S. Obrajyy ◽  
M. Voytovik ◽  
...  
Keyword(s):  
Soil Moisture ◽  
Winter Wheat ◽  
Crop Rotation ◽  
Water Consumption ◽  
Spring Barley ◽  
Black Soil ◽  
Barley Grain ◽  
Reference Level ◽  
Tillage System ◽  
Wheat Germination

The influence of four basic tillage systems and four fertilizer systems on changes in productive soil moisture and water consumption by agrophytocenoses was studied within years 2017–2020 in the fve-feld crop rotation on typical black soil (chernozems) of the Bila Tserkva NAU experimental feld. It is established that the productive moisture reserves in a meter layer of soil in the phase of soybean germination are almost the same for moldboard, differentiated, disk and shallow types of tillage, but quite lower for chisel one; in the phases of the budding beginning and maturity of grain this indicator is the lowest for moldboard tillage, and the highest for moldboardless tillage. In the phase of winter wheat germination, as well as earing and full ripeness of grain, this rate is almost at the same level for moldboard, differentiated and shallow tillage, and for chisel one – 9–12 % higher compared to the reference level; in the phase of spring vegetation restoration no noticeable difference between tillage options was recorded. In the phase of sunflower seedlings there was the largest amount of the productive moisture in a meter layer of soil in the conditions of moldboardless plowing; the rest of tillage have shown almost the same amount of productive moisture; in the phase of the flowering beginning and full maturity of seeds, they are 3–5 % higher for moldboardless plowing, and 2–3 and 4–6 % lower for differentiated and disk tillage respectively than the reference one. In the phases of tube yielding, earing and full ripeness of spring barley grain, it is 11, 5 and 4 % higher compared to the reference rate for moldboardless plowing, differentiated and disk tillage respectively. For moldboard, chisel, differentiated tillage and shallow tillage, the water consumption coefcient of soybeans was 109, 120, 113 and 131 mm/t respectively. With moldboardless, differentiated and disc tillage, it is 11,5 and 4 % higher in winter wheat, respectively, than the reference level. Crop rotation productivity for moldboard and differentiated tillage at the same level, and for moldboardless and disk – signifcantly lower. Key words: crop rotation, crop, tillage, fertilizers, productive moisture, water consumption coefcient, total water consumption, productivity.

Weed community and corn yield variability in diverse management systems

Weed Science ◽  
2006 ◽  
Vol 54 (1) ◽  
pp. 106-113 ◽  
Author(s):  
Richard G. Smith ◽  
Katherine L. Gross
Keyword(s):  
Crop Rotation ◽  
Management System ◽  
Crop Yields ◽  
Cropping System ◽  
Management Systems ◽  
Corn Yield ◽  
Weed Species ◽  
Weed Biomass ◽  
Annual Variability ◽  
Weed Communities

The effects of crop rotation and management system on annual variability in weed communities and crop yields were assessed in a 4-yr study in Michigan. Variability of the weed community and corn yields were assessed using the coefficient of variation (CV) and a multivariate dissimilarity index (Bray-Curtis) that accounted for changes in both weed species abundance and composition. The treatments included two rotations: continuous corn and a corn–corn–soybean–wheat rotation, and two management systems: conventional (CONV) and organic-based (ORG). Weed biomass was significantly higher in the ORG system; however, there was no effect of crop rotation on weed biomass or number of weed species in a treatment (species richness). Annual variability in weed community composition and structure was affected by both crop rotation and management system and was highest in the ORG rotation. In contrast to the weed community, variability in corn yield was highest in the least-diverse cropping system (CONV monoculture), despite that system having a more constant weed community. Corn yield in the ORG rotation was not significantly different from that in the CONV monoculture. Results of this study suggest that management aimed at increasing cropping system diversity may have additional effects on weed communities and crop yields beyond those commonly reported, and these may have important implications for the development of more efficient and sustainable weed and crop management practices.

scholarly journals The effect of intercropping on weed infestation of a spring barley crop cultivated in monoculture

2012 ◽  
Vol 62 (1) ◽  
pp. 163-170 ◽  
Author(s):  
Ewa Kwiecińska-Poppe ◽  
Piotr Kraska ◽  
Edward Pałys
Keyword(s):  
White Clover ◽  
Spring Barley ◽  
Red Clover ◽  
Amaranthus Retroflexus ◽  
Weed Species ◽  
Medicago Lupulina ◽  
Large Fluctuations ◽  
Weed Infestation ◽  
Sonchus Arvensis ◽  
Barley Crop

This paper presents the results of a study carried out in the years 2005-2007 in the Bezek Experimental Farm near the city of Chełm, Poland, on heavy mixed rendzina soil. The effect of intercropping, using red clover (cv. Dajana) and white clover (cv. Astra), on weed infestation of a spring barley crop was studied. The species composition of weeds in the spring barley crop changed to a small extent under the influence of the application of clover intercropping, whereas the population size of particular species showed large fluctuations. In the spring barley crop with the red clover intercrop, <i>Sonchus arvensis</i> occurred in greatest numbers among dicotyledonous weed species. In the barley crop with white clover and without intercrop, <i>Viola arvensis</i> and <i>Sonchus arvensis</i> were the dominant dicotyledonous species. <i>Setaria pumila</i> was the dominant monocotyledonous species in all the treatments. Intercropping using red and white clover clearly limited the growth and development of weeds. The red clover intercrop in the spring barley crop better reduced the infestation with dicotyledonous weeds and also significantly reduced the number of monocotyledonous weeds and the total number of weeds, whereas the white clover intercrop limited only the number of monocotyledonous weeds. The application of the herbicide Chwastox Extra 300 SL significantly reduced the fresh weight of weeds found in the spring barley crop. The presence of the intercrop resulted in different total numbers of weeds in particular treatments. Intercropping distinctly limited the occurrence of the following weed species: <i>Sonchus arvensis</i>, <i>Fallopia convolvulus</i>, <i>Melandrium album</i>, <i>Amaranthus retroflexus</i>, <i>Veronica arvensis</i> and <i>Medicago lupulina</i>. The investigated intercrop species also reduced the biomass of weeds. The application of the herbicide did not differentiate the number of monocotyledonous weeds, which resulted from the application of Chwastox Extra 300 SL that controls only dicotyledonous species.

Relative influence of crop rotation, tillage, and weed management on weed associations in spring barley cropping systems

Weed Science ◽  
1999 ◽  
Vol 47 (1) ◽  
pp. 112-122 ◽  
Author(s):  
Anne Légère ◽  
Nathalie Samson
Keyword(s):  
Crop Rotation ◽  
Analysis Of Variance ◽  
Weed Management ◽  
Management Practices ◽  
Cropping Systems ◽  
Spring Barley ◽  
Life Cycles ◽  
Relative Importance ◽  
Weed Species ◽  
Management Factors

Generalizations concerning the effects of management practices on weed community dynamics often lack robustness, most likely because of the concomitant effects of agronomic and environmental factors. However, such generalizations, when valid, provide useful grounds for predictions and are thus desirable. This study attempted to evaluate the relative importance of crop rotation, tillage, and weed management as factors affecting weed communities and tested the hypothesis of an association between management practices and weeds from certain life cycle groups. Principal component analysis (PCA) of weed density data from a 4-yr field study conducted on a Kamouraska clay and a Saint-André gravelly sandy loam at La Pocatière QC, Canada, identified groups of weed species, while an analysis of variance (ANOVA) of PCA scores associated these groups with management factors. A multivariate analysis of variance (MANOVA) of regression coefficients describing time courses of density for each species confirmed treatment effects. Species segregated roughly according to life cycles. Interactions among weed management intensity, tillage, and crop rotation mostly explained species dominance in the various cropping systems. A first group of species, mostly annual dicots, largely dominated in minimum weed management treatments; their relative importance in each rotation varied with their level of susceptibility to postemergence herbicides. A second group included annuals and perennials, whose commonality seemed to be their tolerance to herbicides; these species also had a particular affinity for chisel and no-till treatments. A third group was formed by perennial species, each with a different response to tillage. The tenuous correspondence between commonly used classification schemes and management factors suggests that other aspects of weed biology (e.g., seed size, dispersal, production, germination requirements, and seedbank longevity) should be considered when trying to explain and predict the presence and dominance of certain weed species with regard to management practices.

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